Offshore method and apparatus



Nov. 23, 1965 J F. MATTHEWS, JR 3,219,116

OFFSHORE METHOD AND APPARATUS Filed Sept. 24, 1963 CLOSURE PLUG FLOW LINEZSCONTGECTION) 2 Sheets-Sheet 1 SCRAPER'PIG TRAP FLEXIBLE JOINT FIG. 2.

INVENTOR. JAM IE F. MATTHEWS, JR.,

T NEY.

FLEXIBLE COUPLING 1955 I J. F. MATTHEWS, JR 3,219,116

OFFSHORE METHOD AND APPARATUS Filed Sept. 24, 1963 2 Sheets-Sheet 2 PIPE SECTIONS WELL CASING FIG- 3- FLEXIBLE JOINT 3m. l6- 2 i |3 l- ADDED PIPE |9 23 INVENTOR.

JAMIE F. MATTHEWSJR v ag E ATT NE Y.

United States Patent 3,219,116 OFFSHORE METHOD AND APPARATUS Jamie F. Matthews, Jr., Grand Isle, La., assignor, by

mesne assignments, to Esso Production Research Company, Houston, Tex., a corporation of Delaware Filed Sept. 24, 1963, Ser. No. 311,017 Claims. (Cl. 16646) The present invention is directed to installation of a flow line for an offshore well. More particularly, the invention is concerned with method and apparatus for use oflshore in connection with a well. In its more specific aspects, the invention is concerned with the installation of a flow line wherein the employment of divers is avoided.

The present invention may be briefly described as a method for installing a flow line for an offshore well or wells wherein a support structure is fabricated having a flow line riser arranged within and attached to the structure. The flow line has a section movably connected thereto arranged outside and releasably attached to the structure. The structure may be fabricated at a point remote from the well site, such as offshore, and then transported to the well site where it is vertically located. Thereafter, one or more wells are drilled from the structure and when the well or a plurality of wells is completed, the movable section is released from the structure and supported at its free end as it is lowered from a vertical position. The movable section has its length extended by sequentially connecting lengths of pipethereto. The movable section is progressively lowered to water bottom as the lengths of pipe are connected to the movable section.

The present invention also is concerned with offshore apparatus for supporting a well or a plurality of wells which comprises a structure adapted to be vertically arranged in a body of water to extend from water bottom to above water surface. A flow riser is arranged within and attached to the structure and is provided with a movable section releasably attached to the exterior of the structure. The movable section is connected to the flow riser by a member which allows the movable section to be pivoted downwardly and outwardly from the structure. The movable section and the flow riser are both sufliciently long to extend the major length of the structure.

The movable section and the flow riser may be suitably connected by a flexible tubular member or by a suitable coupling which allows the movable section to pivot downwardly and outwardly from the structure. The connection between the flow riser and the movable section allows passage of tools to and from the well to which the upper and free end of the flow riser is connected. Such tools chokes, paraflin cutters, pipeline scraper pigs, pipeline scraper balls and soluble scraper plugs, and the like.

The present invention will be further illustrated by reference to the drawing in which:

FIG. 1 is an elevational view of the apparatus of the present invention;

FIG. 1A is a fragmentary view, taken along line 1A- 1A of FIG. 1, showing the pivotal movement employed; FIG. 2 is a partial view of a modification of FIG. 1;

FIG. 3 illustrates the present invention where the movable section is pivoted outwardly and downwardly; and

FIG. 4 illustrates a continuation of the operations of FIG. 3.

Referring now to the drawings where identical numerals will designate identical parts, and particularly to FIGS. 1 and 1A, numeral 11 designates a support structure arranged in a body of water 12 and extending above the water surface 13 from water bottom 14. The structure 11 supports a platform 15, from which a Well or a plurality of wells may be drilled, and a second platform 16, which serves as a production cellar. The structure 11 is ice suitably provided with horizontal braces 17 and cross braces 18. Arranged within the periphery of the structure 11 and attached thereto by suitable attaching means 19a is a flow riser 19 which extends from water bottom 14 to the production cellar 16. The lower end of the flow riser 19 has a curved or bent section 20 which connects by a coupling member 21, such as a Chicksan coupling member which provides for as much as 360 rotation in at least one plane, to a curved section 22 of a movable section 23 which is attached releasably to the outside of structure 11 by suitable attaching means illustrated by numeral 24. These attaching means should be easily accessible from the water surface. The curved sections 20 and 22 are suitably strengthened by bracing members 20a and 22a, respectively. The free end 25 of the movable section 23 is closed by a bull plug 26. The movable section 23 is filled with air to provide vertical buoyancy for supporting same in the water.

Referring now to FIG. 2, the flow riser 19 is connected to the movable section 23 by means of a flexible tubular connection 27, which is suitably a flexible metallic section, which will withstand fluid pressure. The flexible tubular connection 27 allows the movable section 23 to pivot downwardly and outwardly from the structure 11.

Referring now to FIGS. 3 and 4, the structure 11 in the body of water 12 has had a well or a plurality of wells drilled from the platforms 15 and 16, the well having a casing or casings 28 which extends to the platform 16. The flow riser 19 is connected by connecting means 29 directly to the Christmas tree 30 or to the Christmas tree 30 by way of scraper trap 30a when a plurality of wells are drilled from the platform 15. The scraper trap 30a may be of any construction and like the Christmas tree 30 is provided with the usual valves for directing flow.

In FIG. 3, the movable section 23 has been released and pivots downwardly and is connected to a barge by means of a line 31 attached to clamp 32 which, in turn, is clamped around the free end of the movable section 23. Pipe sections 33 are arranged on the barge 30, and these pipe sections are sequentially connected to the pipe section 23 to extend the length thereof. As shown more clearly in FIG. 4, the barge 40 has moved away from the structure 11 in the direction of the arrow, and the movable section has had its length extended by progressively attaching lengths of pipe to the movable section 23 as the barge moves away. The movable section 23 is progressively laid on bottom 14 as the barge moves away and new sections of pipe are added.

Thus, it will be clear from the description taken with the drawing that divers are not required for connecting the well to a flow riser and to the flow line, of which it forms a part. By way of explanation, it is exceedingly difiicult to employ divers at water depths below about feet in that divers can only Work for short periods of time and these shortened periods of time are spaced at long intervals. In other words, the use of divers at depths below 100 feet is time consuming and expensive. The present invention avoids the employment of divers in connecting flow lines and the like to wells drilled from offshore structures. The present invention, therefore, is very important, useful, and has many advantages.

Besides the advantages set out herein, by installing the flow riser inside the support structure, it is protected from contact with boats and vessels. The risers may be securely fastened to the leg or other parts of the structure throughout its underwater length with welded brackets as desired.

Moreover, this installation may be done at a remote location from the well, such as on shore, and the structure transported to the well, either on a barge or by pro viding suflicient buoyancy thereto and floating same to the location.

A still further advantage is that installation of flow lines, in accordance with the present invention, is no longer dependent on mild weather conditions. The installation may be made in water wherein diving is dangerous. In short, so long as a vessel can navigate in the water, the installation may proceed.

The nature and objects of the present invention having been completely described and illustrated and the best mode and embodiment thereof contemplated set forth, what I Wish to claim as new and useful and secure by Letters Patent is:

1. A method for installing a flow line for an offshore well which comprises fabricating a support structure for said well having a flow line riser arranged within and attached to said structure, said flow line riser having a section movably connected thereto arranged outside and releasably attached to said structure, said movable section having a free end, vertically locating said structure at the well site such that said flow line risers and said movable section are in a vertical position with the free end of said movable section in an upper position, releasing said movable section from said structure and supporting the free end of said movable section as said free end is lowered, extending the length of said movable section by sequentially connecting lengths of pipe to the free end of said movable section, and progressively lowering said movable section to water bottom as said pipe lengths are connected to the free end of said movable section.

2. A method for installing a fiow line for an offshore Well Which comprises fabricating a support structure for said Well having a flow line riser arranged Within and attached to said structure, said flow line riser having a section movably connected thereto arranged outside and releasably attached to said structure, said movable section having a free end, vertically locating said structure at the Well site such that said flow line risers and said movable section are in a vertical position with the free end of said movable section in an upper position, drilling said Well from said structure, connecting said well to said flow line riser, releasing said movable section from said structure and supporting the free end of said movable section as said free end is lowered, extending the length of said movable section by sequentially connecting lengths of pipe to the free end of said movable section, and progressively lowering said movable section to water bottom as said pipe lengths are connected to the free end of said movable section.

3. A method for installing a flow line for an olfshore well which comprises fabricating a support structure for said Well having a flow line riser attached to said structure, said flow line riser having a section movably connected thereto releasably attached to said structure, said movable section having a free end, vertically locating said structure at the Well site such that said flow line risers and said movable section are in a vertical position With the free end of said movable section in an upper position, drilling said well from said structure, connecting said Well to said flow line riser, releasing said movable section from said structure and supporting the free end of said movable section as said free end is lowered, extending the length of said movable section by sequentially connecting lengths of pipe to the free end of said movable section, progressively lowering said movable section to water bottom as said pipe lengths are connected to said free end.

4. A method for installing a flow line for an offshore Well which comprises fabricating a support structure for said well having a flow line riser attached to said structure, said flow line riser having a section movably connected thereto and releasably attached to said structure, said movable section having a free end, vertically locating said structure at the Well site such that said flow line risers and said movable section are in a vertical position with the free end of said movable section in an upper position, releasing said movable section from said structure, extending the length of said movable section by sequentially connecting lengths of pipe to the free end of said movable section, and progressively lowering said movable section to water bottom as said pipe lengths are connected to the free end of said movable section.

5. A method for installing a flow line for an offshore well which comprises fabricating a support structure for said well having a flow line riser attached to said structure, said flow line riser having a section movably connected thereto and releasably attached to said structure, said movable section having a free end, vertically locating said structure at the Well site such that said flow line risers and said movable section are in a vertical position with the free end of said movable section in an upper position, drilling said well from said structure, connecting said Well to said flow line riser, releasing said movable section from said structure, extending the length of said movable section by sequentially connecting lengths of pipe to the free end of said movable section, and progressively lowering said movable section to water bottom as said pipe lengths are connected to the free end of said movable section.

6. A method for installing a flow line for an oifshore well Which comprises fabricating at a point remote from the Well site a support structure for said Well having a fioW line riser attached to said structure, said flow line riser having a section movably connected thereto releasably attached to said structure, said movable section having a free end, transporting said structure to the Well site, vertically locating said structure at the well site such that said flow line risers and said movable section are in a vertical position with the free end of said movable section in an upper position, releasing said movable section from said structure and supporting the free end of said movable section, extending the length of said movable section by sequentially connecting lengths of pipe to the free end of said movable section, and progressively lowering said movable section to water bottom as said pipe lengths are connected to the free end of said movable section.

7. A method in accordance with claim 6 in which the structure is fabricated on shore.

8. A method of installing a flow line for an oifshore well wherein a vertically located support structure for said well in a body of water is provided with a flow line riser and wherein said flow line riser has a substantially vertical section movably connected thereto having an upper free end which comprises supportingly lowering the free end of said movable section from its substantially vertical position, and extending the length of said free end while supportingly lowering said movable section to .water bottom.

9. A method in accordance with claim 8 in which the free end of said movable section is accessible from the water surface.

10. A method in accordance with claim 8 in which the movable section is connected to the flow line riser adjacent water bottom.

References Cited by the Examiner UNITED STATES PATENTS 1,393,943 10/1921 Chapman 61-72.3 2,970,646 2/1961 Knapp et a1 -8 X 3,032,105 5/ 1962 Reistle 166-46 3,032,106 5/1962 Focht et al. 166-46 3,055,429 9/1962 Tausch et al. 166-665 3,071,188 1/1963 Raulins 166-666 3,080,921 3/1963 Lacy 166-665 3,125,171 3/1964 Stewart 175-9 X CHARLES E. OCONNELL, Primary Examiner. 

8. A METHOD OF INSTALLING A FLOW LINE FOR AN OFFSHORE WELL WHEREIN A VERTICALLY LOCATED SUPPORT STRUCTURE FOR SAID WELL IN A BODY OF WATER IS PROVIDED WITH A FLOW LINE RISER AND WHEREIN SAID FLOW LINE RISER HAS A SUBSTANTIALLY VERTICAL SECTION MOVABLY CONNECTED THERETO HAVING AN UPPER FREE END WHICH COMPRISES SUPPORTINGLY LOWERING THE FREE END OF SAID MOVABLE SECTION FROM ITS SUBSTANTIALLY VERTICAL POSITION, AND EXTENDING THE LENGTH OF SAID FREE END WHILE SUPPORTINGLY LOWERING SAID MOVABLE SECTION TO WATER BOTTOM. 